What order should a nested sheet cut in so parts do not shift, and how do I force that order?

Why order matters

Every cut-through opens a leak under the sheet and removes material that was holding its neighbors. Production shops on vacuum tables publish the same rule: cut the small parts first, while vacuum is at its strongest, then the large ones. Anything inside a part (holes, pockets, grooves) should be finished before that part is released.

What the software already does

• In a Profile toolpath, inner vectors are always cut before the outer vector that contains them, whatever order you selected them in, so a part stays attached as long as possible.
• The order the machine runs toolpaths in a combined file is the order of the Toolpath list. Use the up and down arrows to change it.

How to force the order you want

1. Run drilling and pocket toolpaths above the cutout toolpath in the list.
2. Put small parts on their own layer and give them their own Profile toolpath. Place it above the toolpath for the large parts.
3. Inside one Profile toolpath, open the Order tab. The choices are Vector Selection Order, Left to Right, Bottom to Top and Grid. If you check several, the software calculates each and keeps the one with the shortest machining time. Check only one when you need a specific sequence.
4. Vector Selection Order cuts in the order you clicked the vectors. Drilling and Pocket toolpaths have the same option as Use Vector Selection Order; unchecked, the software optimizes for time.
5. If you merge toolpaths, Merge By Part finishes each part's inner features before its outline and respects the order of the toolpath list.

Last pass

Shops that onion-skin run the heavy cut on the whole sheet first and take the thin remaining skin afterward, sometimes at half the feed, so little side force reaches a part at the moment it is freed. See the entry on tabs versus onion skin for the settings.

Pro tips

• Ramp into the cut instead of plunging; shops report it puts less force on small parts.
• Dust between the sheet and the spoilboard acts like ball bearings according to production users, so blow the table off between sheets.
• Preview with the toolpaths in list order to watch the sequence before you save.